#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
double fact(int n)
{
	double sum1 = 1;
	for (int x = 1; x <= n; x++)
	{
		sum1 = sum1*x;
	}
	return sum1;
}
int main()
{
	int m = 0, n = 0;
	double result = 0;
	scanf("%d %d", &m, &n);
	result = fact(n) / (fact(m)*fact(n - m));
	printf("result = %.0f", result);
	return 0;
}